TUCSON, Ariz. -- Trying to understand a diagram of arrows, dotted lines and acronyms may sound as pleasurable as watching paint dry, but when it's mapping a potentially revolutionary payment method such as mobile, then for convenience retailers at an annual technology conference, the paint starts looking more like a work of art.

The drudgery of defining terms and mapping out standard processes by which consumers will pay for snacks and gasoline with their cellphones fell to members of the Petroleum Convenience Alliance for Technology Standards (PCATS) in one of a half-dozen working sessions at the group's annual conference in Tucson, Ariz., this week.

In the session on mobile payments, committee members worked to show about 40 conference attendees the progress they made in researching existing standards and developing a proposed process that infused the unique perspective of a petroleum and convenience retailer.

Wesley Burress, the chair of the committee and on staff with the fuels and lubricants IT department at Houston-based ExxonMobil Global Services Co., walked attendees through a set of "business requirements" or statements that defined all the elements surrounding mobile payment, proposed definitions and "use cases" or ways a mobile payment can happen on a technical level.

Identifying "speed to market" as a major goal among many for a mobile-payment standard, Burress said the document needed to cover indoor and outdoor transactions, allow for flexibility to innovate, minimize changes to the retail site, provide an optimal experience for customers and address data security.

He also mentioned several issues that would not be in the standard currently being developed, including signing customers onto the payment program, near-field communications (NFC) or other contactless technologies, the "secure element" within cellphones that can identify the user and loyalty and digital offers.

Some of the definitions that the committee was leaning toward included "mobile payment application" or the "app" that a customer uses to pay, "mobile payments processor" or the supplier of the app, and "mobile device" which could be a cellphone or any other communications-equipped technology.

Other committee members walked attendees through the use-case diagrams. A basic one covered a customer making an in-store purchase. The process mapped out how he or she would initiate a transaction using a payment app, send the request to the proper processor and financial institution for authorization and get approval for the purchase.

Included with the use-case diagram were notes explaining the steps and alternate transaction "flows," including an option that used a complex barcode called a "quick response" or QR code.